Reward for service is an eye opener of the benefits of working for the Kingdom of our God. It gives an insight that your work is not in vain. Every assignment is a high placement in the life of the person God has called. Ofcourse, we are not just created to wake up in the morning, eat, drink and go to work. Instead our Maker and Creator have a designed Purpose for everyone He He created. Ephesians 4;7, "But to each one of us grace has been given according to the measure of Christ's abundant gift."